Fresnel lens and pyroelectricity sensor module including the same

Abstract

A Fresnel lens and a pyroelectricity sensor module are provided. The Fresnel lens includes unit lens groups having different refractive indexes, and each of the unit lens groups includes unit lenses. Between two unit lenses of the same unit lens group at least one unit lens included in a different lens group is arranged. The pyroelectricity sensor module includes a Fresnel lens which condenses infrared light; a detecting sensor disposed to receive the condensed infrared light and detect the infrared light; and a signal processing board on which the detecting sensor is mounted and configured to control an output signal of the detecting sensor. The Fresnel lens includes unit lens groups having different refractive indexes, and each of the unit lens groups includes unit lenses, and between two unit lenses of the same unit lens group, at least one unit lens included in a different lens group is arranged.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority from U.S. Provisional Patent Application No. 61 / 748,917, filed on Jan. 4, 2013 in the United States Patent and Trademark Office, and Korean Patent Application No. 10-2013-0080917, filed on Jul. 10, 2013 in the Korean Intellectual Property Office, the disclosures of which are incorporated by reference herein in their entireties.BACKGROUND[0002]1. Field[0003]Apparatuses, devices, and articles of manufacture consistent with exemplary embodiments relate to a Fresnel lens and a pyroelectricity sensor module including the same.[0004]2. Description of the Related Art[0005]Pyroelectric infrared ray (PR) sensors are employed to detect human motion through detection of a change of infrared rays and are widely used in security fields, electric fields, home automation fields, or other industrial fields. The PR sensor is a pyroelectric device sensor configured to react to an infrared ray having a wavelength of about 10...

AI Technical Summary

Benefits of technology

The patent text describes a Fresnel lens that can be used in a pyroelectricity sensor module. The lens has multiple refraction angles and promotes miniaturization. It includes a plurality of unit lens groups with different refractive indexes, and each group has multiple unit lenses arranged in a radial direction. The arrangement of the unit lenses can be either sequential or irregular. The lens is designed to condense infrared light and the detecting sensor can detect it. The signal processing board controls the output signal of the sensor. The technical effects of this design include improved image quality, reduced size, and improved detection accuracy.

Problems solved by technology

However, the multi-Fresnel lens suffers from a disadvantage in that a total size of a lens is increased in proportion to the number of stacked Fresnel lenses due to a space occupied by each of the Fresnel lenses.

This is not suitable for the recent trend of miniaturization of pyroelectricity sensors.

However, it is understood that one or more exemplary embodiment are not required to overcome the disadvantages described above, and may not overcome any of the disadvantages described above.

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